InGaZnO Thin-Film Transistors on Flexible Substrates

Stretchable sensor arrays have numerous applications in robotics, structural health monitoring (SHM), and electronic textiles. The ability to fabricate thin-film transistor (TFT) active devices for stretchable sensor arrays opens up new possibilities in data acquisition and conditioning. TFT active devices for stretchable sensor arrays require fabrication on polymer substrates, which introduces new process challenges due to thermal limitations, which ultimately limits the TFT performance. In this research, we demonstrate low-temperature fabrication processes for amorphous oxide semiconductor (AOS) TFTs, using room-temperature RF sputtering for deposition of InGaZnO and Silicon Nitride thin-films on a polyimide substrate. These devices have comparable performance to AOS TFTs fabricated on rigid substrates, having an electron mobility exceeding 10cm2/ (V s), and an on-off current ratio of 106.